In order to maintain the health of the animal colony, principles of animal husbandry that provide an ideal environment for the animals is essential. Consistent with federal mandated practices, the requested equipment will maximize the comfort and health of the animals, minimize moisture and ammonia levels in the cages, and provide an effective barrier from possible pathogens. The requested individual ventilated caging provides an ideal microenvironment for the animal. We currently have two ventilated racks and the requested racks will replace the four stainless steel racks, thus allowing 100% of the rat population to be housed in individual ventilated caging. Housing rodents in ventilated racks like Sealsafe Plus will protect them from infective agents and protect the animal users from allergens and requires a high volume of air to be blown into the cages so as to provide the optimal micro-environment, thus aiming to maintain a low concentration of ammonia, carbon dioxide and a stable concentration of oxygen.